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Lämpliga stampopulationer av mellanspett (Dendrocopos medius) för återintroduktion i Linköping, Östergötland / Suitable source populations of the middle spotted woodpecker (Dendrocopos medius) for reintroduction in Linköping, Östergötland countyEriksson, Viktor January 2019 (has links)
The middle spotted woodpecker (Dendrocopos medius) became extinct in Sweden in 1982. The last population inhabited a fragmented area of 300 km2 and were for a long time a characteristic species for the oak stands of Sturefors and BjärkaSäby, south of Linköping. The reason why the species got extinct depends mostly on habitat fragmentation. Also, the extinction got hasten by harsh wintering conditions. The purpose of this study is to evaluate which of current populations of Dendrocopos medius could best serve as source of founders for a possible reintroduction of the species in Linköping. Populations from Poland, Germany, Latvia and Lithuania were considered, taking their ecology, phylogeny and genetic diversity into account. The population’s abiotic conditions, in combination with their ability to adapt to different habitat was also considered crucial to conduce a successful reintroduction of middle spotted woodpecker in Linköping. Populations from Bialowieza and Krotoszyn in Poland, Wolfsburg in Germany and Kaunas and Marijampole in Lithuania were considered most suitable to contribute with founders. Since the middle spotted woodpecker could work as a flagship species for old and open oak stands, a reintroduction of the species could turn up the awareness for nature conservation, species conservation and biodiversity.
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Alteration of behavior by desert bighorn sheep from human recreation and Desert Bighorn Sheep Survival in Canyonlands National Park: 2002 - 2010Sproat, Kanalu K. 04 December 2012 (has links) (PDF)
Human encroachment into wilderness areas can influence the persistence of wildlife populations by decreasing and degrading habitat, displacement, and decreasing survival. For bighorn sheep (Ovis canadensis), some human activities are detrimental, causing both physiological stress and habitat abandonment. Between 1979 and 2000, human recreation has increased over 300% in areas occupied by desert bighorn sheep (O. c. nelsonii) in southeastern Utah. We investigated if an increase in human activity in areas used by bighorns affected their behavior. We observed 34 bighorn sheep using focal-animal sampling for >14 hrs to compare time spent grazing and scanning between areas of high and low human use. We identified group size, presence or absence of a lamb, distance to escape terrain, and human use (high versus low) as potential explanatory variables that influenced grazing and scanning times, and created an a priori list of models based on these variables. We used Akaike's Information Criterion adjusted for small sample sizes (AICc) to rank models, and used model selection to find a best approximating model (lowest AICc value) for both behaviors. Desert bighorn sheep spent less time grazing and more time scanning in high human use areas (22% grazing, 29% scanning) than in low human use areas (54% grazing, 8% scanning). Caution should be taken when considering which areas or trails should be opened during these important seasons to minimize and reduce additional stresses to bighorns caused by human activity. Bighorn sheep populations experienced significant declines after European settlement in North America. Today, the primary practice of bighorn sheep conservation is through population restoration and augmentation from remnant source populations. We conducted a 9-year telemetry study for a source population of desert bighorn sheep in Canyonlands National Park, Utah. We captured and collared 58 bighorn sheep from 2002-2009. To estimate annual and seasonal survival, we used known-fate analysis in Program MARK 4.1. We used model selection to test hypotheses for bighorn survival, including sex, age, human use, year, and month, as possible explanatory variables. There were 20 mortalities during the study. Annual survival ranged from 83% - 88% with no significant variation among any of the years. Model selection results showed that the top six models included a temporal variable (e.g. season or month), and carried 92% of the AICc weight. Population persistence for bighorn sheep can be compromised by high levels of predation, habitat fragmentation, and disease transmitted from domestic sheep. We suggest that land managers continue to maintain the separation of domestic sheep from bighorns in CNP. We also recommend that survival studies continue to ensure that future translocation projects do not occur at the expense of the source population.
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